This contributor to Deviantart had this idea that on eyeball Earths some plants might grow in the shadow of bigger plants and get energy from the wind, like a naturally occurring wind turbine.
My question is: does anyone have any idea how that could actually work? Is there some way kinetic energy could be stored as chemical? Or at least a natural example?
Piezoelectric materials in their "leaves" can convert the deformation of the leaves into electric charges.
Once you have charges in molecules it is "just" a matter of chemistry and cascading that energy into another molecule, like it is done with photosynthesis.
Piezoelectricity is the electric charge that accumulates in certain solid materials (such as crystals, certain ceramics, and biological matter such as bone, DNA and various proteins) in response to applied mechanical stress.
Windstalks:
The plants would look something like this, at a guess. https://vortexbladeless.com/ or https://atelierdna.com/portfolio/windstalk/ While I can't say the exact method of storing the mechanical energy as chemical energy, you could probably have evolution make conductive materials that would generate electricity via piezoelectric disks (engineers, feel free to give more specific details please) to charge simple chemical batteries, or store compression in mechanical spring-like mechanisms that generated chemical energy by using this stored power to push against some kind of molecules generating ATP. These power methods are still conceptual, so a lot of the bugs haven't been worked out, let alone applying them to generating stored chemical energy. Still, where there is energy, nature finds a way.
